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201.
The present study’s aim was to test a German guideline for farm’s self-monitoring in sows and piglets for its feasibility as well as its interobserver and test–retest reliability. The study was performed between September 2016 and April 2018 on 13 farrowing farms in Northern Germany. Contrary to the guideline, the testing was not carried out by the farmers themselves but by 2 observers with experience in pigs representing common farmers. For the interobserver reliability study, the observers performed 20 joint farm visits independently assessing the same animals. For the test–retest reliability study, each farm was visited 5 times by 1 observer (day 0, day 3, week 7, month 5, month 10). Farm visit 1 (day 0) was used as reference and compared with the remaining farm visits. The reliability was evaluated using Spearman’s rank correlation coefficient (RS), intraclass correlation coefficient (ICC), and limits of agreement (LoA). As results, the guideline’s feasibility was limited. The indicators’ reliability also presented divergent results: All indicators in piglets revealed acceptable to good interobserver reliability (RS 0.64 to 0.77 ICC 0.33 to 0.48 LoA between the intervals −0.02 to 0.13 and −0.02 to 0.00). Contrarily, interobserver reliability was low for indicators in sows (e.g., claw alterations: RS −0.41 ICC 0.00 LoA −0.97 to 0.68). Overall acceptable test–retest reliability could be assigned to all indicators although no exact agreement existed but only the pursuit of trends is indicated. On the basis of the present results, the guideline in its present form cannot be recommended for farms’ self-monitoring. Given the restricted applicability, it should be reconsidered whether it might not be more appropriate to use scientifically tested and generally accepted animal welfare assessment systems such as the Welfare Quality animal welfare assessment protocols, although their application is also time-consuming. 相似文献
202.
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204.
Electrospinning is emerging as a simple means of producing fibers with diameters ranging from 0.02μm to many microns. Electrospinning, however, relies on the force generated by an electric field on the surface of a polymer
solution to either enhance instabilities in a thinning jet or to rapidly elongate a jet of polymer solution form a nozzle.
In this article, the fundamental physics and fluid dynamics on the subject matter are described, and some of the relevant
parameters in electrodynamic instabilities at polymer interfaces are discussed in some detail. 相似文献
205.
Zusammenfassung Die physiologische Alterung der Pflanzknollen durch Lagerung bei überoptimalen Temperaturen (jahresunterschiedlich 16–29,5°C,
1988–90 vor dem Pflanzen abgekeimt, 1991 vorgekeimt wie Kontrolle) führte im Vergleich zur vorgekeimten Kontrolle im Mittel
von 25 Sorten in allen Versuchsjahren zu einer Verminderung der Bestandesdichte und des Ertrages. Eine Gruppe von Sorten erwies
sich in allen Jahren als relativ tolerant gegen die Alterung, eine andere als signifikant empfindlicher, dazwischen lag ein
breites Mittelfeld mit zum Teil erheblichen Schwankungen in den Jahren. Die Reaktion der Sorten zeigte keine Beziehung zu
ihrer Reifegruppe und ihrer Keimintensit?t, dagegen war die sortentypische Ertragsdepression nicht sehr eng, aber signifikant
mit dem Schwund w?hrend der Lagerung korreliert.
Summary Seed tubers were stored at above optimal temperatures. Mean temperatures varied during test years from 16 to 29.5°C (in 1988–1990 tubers desprouted before planting; in 1991 chitted tubers as in control; Table 1). This procedure of physiological ageing of seed tubers resulted in reduced plant density and lower yield compared to the chitted control in every year of the test period (average of 25 cultivars). The emergence was significantly delayed as compared to the control in all years (Table 2). Assessed for yield, the cultivars Désirée, Sanetta, Astilla and Andra showed a significantly higher degree of tolerance to warm storages (>80%, when compared to the control) than the cultivars Arkula, Dorisa, Karlena and Koretta (<25%; Table 3). Between these two extremes there was a large number of intermediate levels of tolerance, a result of fluctuating reactions of various cultivars to changing conditions in the years of the test period (Fig. 1). No correlation could be found between the cultivars' reactions and their maturity group or their sprouting behaviour. There was, however, for each cultivar a significant negative correlation between loss in weight through transpiration and respiration and plant density and yield (r=−0.55 and −0.54; Table 4). Plant density and yield were closely correlated (Table 4). The regressions between loss of plants and reductions in yields show that after seed tuber storage at higher temperatures a reduced yield must be expected even when plant density is not reduced (loss of plant 0%; Fig. 2). With complete stands, the use of physiologically aged seed tubers that were desprouted before planting (1988–1990) resulted in a reduction of yield of 17–20%; when old seeds were chitted as in control a loss in yield of 15% was calculated.相似文献
206.
Jens Botterweck Burkhard Schmidt Jan Schwarzbauer Roschni Kalathoor Andreas Schäffer 《Biology and Fertility of Soils》2014,50(7):1015-1024
We studied the influence of an immobilized laccase from Trametes versicolor on non-extractable residue (NER) formation of the systemic fungicide 14C-metalaxyl in soil. We added the enzyme (130 mU/g DW) to soil sterilized by gamma irradiation and observed that the amount of NER (6.3 % of applied radioactivity) after 10 days of incubation was enhanced about twofold compared to the sterile soil without laccase addition. Residues formed within samples without enhanced enzyme activity were mainly bound via ester linkages to all fractions of humic matter, i.e., fulvic acids, humic acids, non-humines, and humines, respectively. In contrast, residues formed in presence of immobilized laccase were more strongly bound by covalent linkages such as ether and C-C bonds, especially to humic acids. After chemical degradation of the humic matter, it could be observed that all NER contained the first major transformation product, i.e., metalaxyl acid. The findings underline that the residue formation of metalaxyl in soil may be partly catalyzed by immobilized extracellular oxidative enzymes through oxidative coupling reactions within the humic matter. 相似文献
207.
Between 1996 and 2007 31 experiments with 34 herbicides were carried out in peppermint in experimental stations and on peppermint fields of Thuringian farms. The main objective of the tests was to get the necessary data for the authorization procedure according to the regulations of §?18a PflSchG. Peppermint plants are susceptible against some herbicides like Callisto, Monitor. Other herbicides like Afalon, Basta, Boxer, Centium 36 CS and Roundup Ultra can cause severe damages on peppermint if they are applied to the false stage of development of the plant. The use oft the herbicides Basagran, Fusilade MAX, Lentagran WP, Lontrel 100 and CLIOPHAR 100 is authorized for the application in peppermint according the regulations of §?18a PflSchG. The herbicides Bandur, Boxer, Stomp SC and Targa Super can be used in peppermint according the regulations of §?18b PflSchG. Further experiments with herbicides in peppermint are intended to the authorization to more herbicides and to unsolved problems with the weed control like for example the often insufficient effects of the recently authorized herbicides against Solanum spp., Galinsoga spp., Polygonum spp. and other weeds. 相似文献
208.
The effect of a continuous duodenal infusion of L-histidine (His) (8 g/d) on the retention of nitrogen was investigated in two experiments (I, II), each of which was carried out using two young bulls. In Exps. I and II, the animals (150-250 kg BW) were fitted with a re-entrant cannula in the proximal duodenum and were fed diets containing 125 g CP/kg DM and 11.5 MJ ME/kg DM. A third experiment (III) using two young bulls (140-200 kg BW) fitted with a simple T-cannula was carried out infusing 6 g L-His. The animals were fed a low protein diet (94 g CP/kg DM and 11 MJ ME/kg DM). The study was done to find out whether or not L-His is the first limiting amino acid (AA) for growing ruminants. N retention was 28 and 31, 38 and 38, 22 and 24 g/d without L-His infusion and with L-His infusion for Exps. I, II and III, respectively. Both in the experiments with a standard protein supply (I, II) and in the experiment with reduced protein supply (III), no significant differences were found between periods with and without infusion of L-His. The utilisation of duodenal NAN varied between 39% and 50% and was also not significantly influenced by the duodenal infusion of L-His. No significant effect was observed on the flow of AA into the duodenum. The faecal excretion of AA was also not significantly influenced by the infusion of L-His. The utilisation of individual amino acids as calculated by the ratio of retained AA to intestinal apparently digested AA, did not differ significantly following the duodenal infusion of L-His. As expected, the utilisation of His decreased. Of the different essential AA, L-His was the most utilised (80%) followed by Arg (72%), Met (60%), Leu (45%) and Lys (44%), during periods without supplementation of L-His. It is concluded that the intestinal supply of L-His from the basal diet was sufficient for the potential growth level of animals under these experimental conditions. In all AA present at the proximal duodenum, L-His could have at first a limiting effect on the performance of growing young bulls with high body gain. Arg and Met, but not Lys, could be second or co-limiting AA. 相似文献
209.
210.
von Altrock A Schütte A Hildebrandt G 《Berliner und Münchener tier?rztliche Wochenschrift》2000,113(5):191-201
Reports of human salmonellosis caused by the consumption of pork and the introduction of control and surveillance programmes in different countries of the European Union were the reason for carrying out an international study under the title "Salmonella in Pork (Salinpork)": Six different EU-countries were involved in this study, which was supported by the Commission of the European Community and which was carried out over a period of April 1996 to April 1999. The aim of the investigation presented was to determine the prevalence of Salmonella in fattening, breeding and farrow-to-feeder herds as well as the determination of risk factors for the introduction of Salmonella into the farm (Part 1). In addition, sources of contamination of pork should be detected by taking samples of the product and the environment in the slaughterhouse (Part 2). In Germany, the investigation into Salmonella infections of 60 fattening, 20 breeding and 20 farrow-to-feeder herds were carried out in Schleswig-Holstein. The investigation included bacteriological examinations of feed and faecal samples for sero- and phagetyping and serological examinations by using the Danish Mix-ELISA. From 2,947 serological investigated fattening pigs were 7.3% (n = 213) positive, from 797 breeding sows 9.2% (n = 73) were serological positive and 4.5% (n = 18) of the investigated sows (N = 399) in farrow-to-feeder herds were serological positive. Altogether, 28.3% of the fattening, 50.0% of the breeding and 15.0% of the farrow-to-feeder herds were serological positive. A questionnaire was used to capture data about management, hygiene measures, feeding systems and the occurrence of diseases in the herd. After statistical analysis the common risk factor of fattening herds and sow herds was the use of pelleted feed. But in a control study with 17 different fattening herds the result could not be proven. Other factors which can influence the occurrence of Salmonella infections were discussed. 相似文献